Major Depressive Disorder

Major depressive disorder (MDD) has been ranked as the third cause of the burden of disease worldwide in 2008 by WHO, which has projected that this disease will rank first by 2030. It is diagnosed when an individual has a persistently low or depressed mood, anhedonia or decreased interest in pleasurable activities, feelings of guilt or worthlessness, lack of energy, poor concentration, appetite changes, psychomotor retardation or agitation, sleep disturbances, or suicidal thoughts. Per the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5), an individual must have five of the above-mentioned symptoms, of which one must be a depressed mood or anhedonia causing social or occupational impairment, to be diagnosed with MDD. History of a manic or hypomanic episode must be ruled out to make a diagnosis of MDD. Children and adolescents with MDD may present with irritable mood.

Per DSM-5, other types of depression falling under the category of depressive disorders are:

1. Persistent depressive disorder, formerly known as dysthymia

2. Disruptive mood dysregulation disorder

3. Premenstrual dysphoric disorder

4. Substance/medication-induced depressive disorder

5. Depressive disorder due to another medical condition

6. Unspecified depressive disorder